The Holy Roman Empire, also known as the Roman Empire (before 1157) and the Holy Roman Empire of the German Nation (from 1512), was a European superpower throughout the 2nd millennium CE that dominated the central European continent.
Its counterpart in the east was the Byzantine Empire.
The spiritual successor to Charlemagne's Frankish Empire, itself a successor to the Western Roman Empire, the Holy Roman Empire's dominion extended from Denmark in the north, through Germany, and into northern Italy. By 1459, the Empire encompassed numerous city states, such as Milan and Florence, which allowed the Auditore International Bank to provide services throughout the Empire, and the Kingdom of Germania. Despite this dominion, the Empire's military presence in Italy was negligible.
During the reign of Emperor Maximilian I, the Empire developed an antagonistic relationship with the Borgia Papacy, stemming from the Pope recruiting Swiss mercenaries who had defeated him in the Swabian War into the Papal Guard. After the Italian Assassins kidnapped these mercenaries and delivered them to Maximilian in Vienna, the shocked but grateful Emperor had them form the Landsknechte, and later promised they would aid the Assassins should they ever request it.
The Renaissance partly began in the Holy Roman Empire after Johannes Gutenberg invented the printing press, and under Maximilian, culture, science and reform blossomed with German, Dutch and Swiss intellectuals like Conradus Celtis, Martin Luther, Desiderius Erasmus and Bombastus, some of whom became members or allies of the Assassins (Erasmus in particular became leader of the Northern European Assassins).
This scientific growth extended to the reign of Rudolf II during the late 16th/early 17th century, who invited the occultists John Dee and Edward Kelley to his court in Prague. However, encouraging such pursuits came with a price, as during Rudolf's reign the Golem was unleashed on the city, to which he was criticized for allowing too much intellectual freedom.
By the 18th century, the Empire had fractured, becoming little more than a disparate collection of loosely-affiliated states: mercenaries from a number of German states, such as the Jägers fought on both sides of the American Revolutionary War.
During the French Revolution, the fall of Louis XVI and the House of Bourbon worried the empire. Soon, a war has been declared against the French Republic, and the conflict lasted 10 years, until another war began. Eventually, the empire had in collapsed during the conflict. 
- ↑ Assassin's Creed: Renaissance
- ↑ Assassin's Creed II
- ↑ 3.0 3.1 Assassin's Creed: Project Legacy - Contracts
- ↑ Assassin's Creed: Revelations
- ↑ Assassin's Creed: Revelations novel
- ↑ Assassin's Creed: Project Legacy - Divine Science: Chapter 3 - Elizabeth Jane Weston
- ↑ Assassin's Creed III
- ↑ Assassin's Creed: Unity